The 2008 TE's have a UFO led unit in the p/u kit. It is a tail/brake light that has DOT on it. Looks like this 1 here. http://www.oemcycle.com/Item/product/5186/
If it's for the 2004 in the sig line, then I believe head light & tail light are run on AC. Only LED light I've found that'll work without some custom wiring is the DRC EDGE II.